1. Technical Field
The present invention relates to a touch panel.
2. Description of the Related Art
As a computer using a digital technology is developed, accessory devices of the computer have also been developed. A personal computer, a portable transmission device, and other personal only information processing devices, or the like, perform text and graphic processing using various input devices such as a keyboard, a mouse, or the like.
However, as an information-oriented society is rapidly progressed, a usage of the computer has gradually expanded. It is difficult to efficiently drive products only by the keyboard and the mouse serving as the present input devices. Therefore, a need for devices that are simple and have little malfunction while allowing anyone to easily input information is increased.
In addition, a technology for an input device has been evolved to a technology of high reliability, durability, innovation, design and machining, or the like, including a technology of satisfying general functions. In order to achieve the above objects, a touch panel as an input device capable of inputting information such as text, graphic, or the like, has been developed.
The touch panel is installed on a display surface of a flat panel display, such as an electronic notebook, a liquid crystal display device (LCD), a plasma display panel (PDP), electroluminescence (El), or the like, and an image display device, such as a cathode ray tube (CRT), which is a tool used for a user to select desired information while watching an image display device.
FIG. 1 shows a cross-sectional view of a touch panel according to the prior art and FIG. 2 shows a perspective view of a touch panel shown in FIG. 1. Referring to FIGS. 1 and 2, a touch panel 100 according to the prior art includes transparent substrates 110 and 120, transparent electrodes 115 and 125, and electrode wirings 117 and 127 and further includes an FPC 130. That is, the first transparent electrodes 115 and the second transparent electrodes 125 are formed on surfaces of each of the first transparent substrate 110 and the second transparent substrate 120 that faces each other are provided with and the first electrode wirings 117 electrically connected to the first transparent electrodes 115 are formed at edges of the first transparent electrodes 115 and the second electrode wirings 127 electrically connected to the second transparent electrodes 125 are formed at edges of the second transparent electrodes 125. The first electrode wirings 117 and the second electrode wirings 127 are concentrated on side ends of the transparent substrates 110 and 120 and the separately disposed FPC 130 is connected to the first electrode wirings 117 and the second electrode wirings 127 and transmits electrical signals to a controller (not shown).
The transparent substrates 110 and 120 configuring the touch panel 100 according to the prior art are partitioned into an active region in which the transparent electrodes 115 and 125 are formed and an inactive region in which the electrode wirings 117 and 127 are formed. The transparent electrodes 115 and 125 are configured to serve to sense a touch input position of a user. In order to more accurately sense the touch position, there is a need to densely dispose the transparent electrodes 115 and 125 that are formed in a predetermined area of the active region. Therefore, the number of electrode wirings 117 and 127 electrically connected to the transparent electrodes 115 and 125 is also increased, such that an area occupied by the inactive region may unnecessarily extend in the transparent substrates 110 and 120.
Meanwhile, a demand for a transparent conductive layer material has also increased with a sudden expansion of a thin display field business, centering around an LCD. As the transparent conductive layer material, indium tin oxide (ITO) has been mainly used. When considering the rising demand for applications due to excellent characteristics of the ITO as a transparent electrode, it is expected that the consumption of the material is gradually increased in the future. However, indium forming ITO is a representative one of scarce and depleting resources and the supply thereof is greatly reduced. According to the specialist, it is expected that the indium is fully exhausted from about 10 to about 25 years. The indium needs to be purified using by-products of a zinc ore, which also leads to high scarcity. Even before the indium is depleted, the sudden rise in indium price leads to increase manufacturing costs of applications. Therefore, a development of a new transparent conductive layer that does not include the indium is very urgently needed.